Selective calling-key.



M. F. GEER & R. 0. LEAKE.

SELECTIVE CALLING KEY.

ABPLIOATION FILED D20. 22, 1910.

1,076,278. Patented Oct. 21, 1913.

5 SHEETS-SHEET 1.

INVENTORS.

ATTORNEY.

WITNESSES:

M. F. GEBR & R. G. LEAKE.

SELECTIVE CALLING KEY.

APPLICATION FILED DEC. 22, 1910.

Patented Oct 21,1913

6 SHEETS-SHEET 3.

CENTER LINE.

L/ CENTER \JNE m /1m7//77// Lid 1777/ /T/ A TTORNE Y.

M. I. GEHB, &' R. c. LEAKE.

' SELECTIVE CALLING KEY.

APPLIOATIOR' FILED 11110.22, 1910.

Patented Oct. 21, 1913.

5 SHEETS-SHEET 4.

Mm FIG-.4. QMAXIW zf m WITNESSES 7' I ATTORNEY.

SELECTIVE CALLING KEY.

APPLICATION FILED DEC. 22. 1910.

Patented Oct. 21, 1913.

5 SHEETS-SHEET 5.

HI T0 STA RTING R ELAY TO '1). cimm he. 60 MOTOR-GENERRTOR SET.

u l FIGmS. 5+

I A' WM 7 m W1T vsss.- INVENTORS.

ATTORNEY.

I UNITED s'rAns MAURICE F. GEER AND RICHARD C. LEAKE, OF ROCHESTER, NEWYORK, ASSIGNORS TO GENERAL RAILWAY SIGNAL COMPANY, OF GATES, NEW YORK, ACORPORATION 013 new YORK.

SELECTIVE CALLING-KEY.

Specification of Letters Patent.

Patented Oct. 21,1913.

Applicationv filed December 22, 1910. Serial No. 598,673.

To all whom it may concern Be it known that we, MAURICE F. Gene andRICHARD C. Luann, citizens of the United States, and residents of thecity of Rochester, in the county of Monroe and State of New York, haveinvented a new and useful Selective Calling-Key, of which the followingis a specification.

This invention relates to that class of devices whereby a varying numberof impulses of electricity of opposite polarity may be impressed uponline wires to operate selectively upon appropriately constructed devicesat remote stations.

The devices to which tl is invention relates are in the electrical arttermed selective calling keys, and this invention therefore broadlyrelates to a selective calling key.

The primary object of the invention is to construct a device of thecharacter described that wiil enable an operator at a central station-tocall any one of a large number of remote stations by as few and. simpleoperations as is consistent with the complexity of a selectiye callingsystem.

A further object of the invention is to so construct a selectingtransmitting key that the mental task required of an operator inperforming the operations necessary to call a remote station is slight,the construction of the transmitting key being such that the necessityfor the so called code call is entirely eliminated, substitutingtherefor simple operations, such as the pressing of only two buttonsonce each and the turning of a crank.

A further object of the invention is to so construct a device of thecharacter stated that undue haste in transmitting the impulses ofelectricity to the lineslby the operator, thereby causing faultyoperations of the devices at the remote stations is entirely preventedby means inherent in the mechanism.

A further object of the invention is to so construct a device of thecharacter stated that all parts will automatically return to theirnormal positions ready for another calling operation, after one call hasbeen made.

A further object of the invention is to so construct a device of thecharacter stated that one kind of current may be impressed upon linewires for operating the selective devices at remote stations and anotherkind of current may be impressed upon line wires for operating'anaudible alarm at remote stations after the selector device at'thatstation has itself been operated.

A further object of the invention is to provide means independent of thewill of the operator to prolong the audible alarm at the remote stationsfor such a time as is deemed best in order that attention will surely beattracted.

A further object'of the invention is to assemble in a unitary structure,occupying but small space and comprised of but relatively few parts, allof the mechanisms for accomplishing the abovenamed objects.

A further object of the invention is to construct the device foraccomplishing the above named objects in a substantial and durablemanner, and to so connect the various parts of the assembled key that itmay be readily taken apart for the purposes of inspection or repair, andwhen so taken apart that all of its .parts shall be readily accessible.

T he invention consists in the constructions, combinations andarrangements herein shown, described and claimed.

In describing the inventionin detail reference will be had to figure-sof the drawings and the characters of reference thereon,

in which:

Figure l is a top View looking in a direction at right angles to theface of the key. Fig. 2 is a cross sectional view on the line 2-2 ofFig. 1 looking in the direction of the arrows. Fig. 3 is a longitudinalsectional view on the line 33 of Fig. 2 looking in the direction of thearrow. Fig. 4 is a longitudinal sectional View on the line of Fig. 2looking in the direction of the arrow. Fig. 5 is a diagrammatic Viewillustrating the circuits controlled by the key. Fig. 0 is a crosssection showing the construction of a crank handle used in the device.Fig. 7 is a view partly in section of a push key used in the deviceshown in normal position. Fig. 8 is a View showing the parts asillustrated by Fig. 7 in another position. Figs. 9, 10, 11 and 12 aredetailed views showing the different relative positions of tongues onthe sectors forming a part of the device.

U0notruct2'0n.1 designates a cast metal frame forming the supportingstructure for the operating parts and is composed of the base 1 whichmay space 5 in which those parts which it is de-' sired to protect fromoutside interference may be inclosed.

'6 and 7 designate bearings cast integral with the frame; 8 designates ashaft one end of which extends through the face plate 2 and bears acrank 9 which is pinned thereto by means of pin 10, the other end ofwhich shaft is journaled in bearing 6; 11 designates a gear wheelrigidly attached to shaft 8 and meshing with a pinion 12, which isrigidly at tached to the gear 13, both of which revolve upon a studfastened in bearing 7; 14s designates a pinion revolubly mounted uponshart 8 and having rigidly attached thereto friction shoe bearing member1 1 which has two arms 15 and 16 to each of which is attached by meansof pins 17 the brake shoes 18-18. The ends of the brake shoes 18-18 notattached by means of the pins 17 are held inwardly by means of thetension springs 19, one end of each spring being attached to members 18,the other ends of the springs being attached to the opposite ends of acurved intermediate member 20, the brake shoes 18-18 having slotted ends18 in which the arms 15 and 16 are inserted to hold the brake shoes inposition; 18 designates fiber pieces fastened to the brake shoes toincrease their adhesion to the brake drum 21; which is rigidly attachedto the hearing 6.

22 designates a hub pinned by means of pin 23 to shaft 8 and bearing anoutstanding arm 24, to which is attached the extension arm 25 hearingthe insulating block 26, fastened thereto by means of the screws 27,which block bears the contact springs 28, 29, 30 and .31, each springcomprising two fingers which bear upon the metallic strips 3 1 and 35fastened to the back face of an insulating disk 36 best shown in Fig. 4;37 and 38 are spacing and supporting members to space the disk 36 fromthe face plate and to support. the same, the spacing posts beingfastened to the face of the plate by the screws 39 and the disk beingfastened to the posts by the screws 40 best shown in Fig. 4. To the backfacc'of the disk are also attached by means of screws the curved strip11 and the small segmental strips 12, 43, lst, 415, 4:6, 4:7, 18, a9,50, 51, 52, 5s, 54, 55 and 5c; 57

designates a wire connecting strip 49 with strip 34; 58 designates awire connecting strip 32 with strip 41.

59 designates awire connected to the strip 34 at one end and to one poleof a source of direct current at the other 60 designates a wire one endof which is connected to strip 32 and the other end of which isconnected to the other pole of the same source of direct current; 59 and60 both being connected to one pole of a source of alternating current;61 designates a wire connected to strip 33 at one end and contact spring128 atthe other; 63 designates a wire connected at one end to strip 35and at the other to a contact spring 152; 65, 06, 67, 68, 69, and 71designate contact springs each of which is normally in contact with ashorter contact spring as 72 shown in Fig. 2, all of these springs 65,66, &c., and the co-acting springs 72 being held in place by means of apost 157 fastened to the face plate by means of the screw 158, thesprings being held in place thereon by screw 159 and which has aninsulating bushing about it, not shown, being insulated from the post157 and from each other by means of insulating washers 160, 161 and 162.Each of the lower springs as 65 is upper spring as 72 as best shown inFig. 5 by ribbon copper 163. On the other side of the device a similarset of springs is arranged, the upper springs being designated 72 andthe lower springs being designated 73, 74, 75, 65, 77, 78 and79respectively.

Each of the lower springs in both sets are adapted to contact with andbe moved out of engagement with the top springs 72 by means of the pushkeys 80, 81, 82, 83, 84, 85,

86, 87, 88, 89, 90, 91, 92, 93, 94:, 95; 96 designatcs an insulatingbone tip on the end of each push key, which is adapted to contact withthe lower contact springs before mentioned. Just above the insulatingbone tip 96 on the same spindle 99 therewith is a cone shaped member 97having a shoulder 98 at the base of the cone; 100 designates a knobfastened to the top of spindle 99 which is slidingly mounted within thecavity 101 of the cup shaped member 102 which is pressed connected tothe adjacent into the face plate 2; 170 designates a compression springplaced between the knob 100 and the bottom of the cup shaped member 102,so that the knob is normally held upwardly, which, of course, also holdsup the cone shaped member 97. Each of the coneshaped members 97 restswithin the counter sunk holes 103 of the sectors 104 and 105.

106 and 107 designate hubs which bear the arms 108, 109, 110, 111 whichsupport the sectors 104 and 105. These hubs are journaled on a bushing112 best shown in Fig.

4;, which is rigidly attached to the face plate 2 by means of the threearms 113 and the screws 11 1, the hub encircling the shaft 8 rea ers andforming a bearing for the same; 115

and 116 designate arms best shown in Fig; 1, which depend from thesectors 1 04 and 105 respectively, and which pass through the bifurcatedends of levers 1 17 and 118, which leversbea'r upon their other end theinsulating sleeves 119 and l'20 best shown in Fig. 3, which are held inplace upon the levers by means of the screw threaded ends and the nuts121 as shown in Fig. 2, the levers being pivoted on the posts 122 andheld in place thereon by means of the screws 123 and having-a constanttension exerted upon them to force them in the direction of the arrow Ain Fig. 3 caused by springs 124. The insulating sleeves 119 bear againstcontact springs 125 and 126 and cause spring 125 to contact with spring127 when moved in the direction of the arrow B when the arm 117 iscaused to move by depressing one of the push keys as 80 on the left handside of the face of the transmitting key. The

spring 126 being also made to contact with spring128 when the lever 118is moved in the direction of thearrow B by the operation of one of theu'sh keys as on the right hand side of the ace of the device. Back ofsprings 126 and 128 as shown in Fig. 3, are a similar set of springs 151and 152 all of which together with springs 126 and 128 are mounted on ablock of insulating material as 164, which is fastened to the back 1 ofthe frame. The springs 125 and 127 being likewise mounted on insulatingblock 165 fastened to the back 1 of the frame.

The cone shaped members 97 resting within the counter sunk holes of thesectors 104 and 105 and bearing against one edge of the holes 103therethrough will, upon being depressed, cause the sectors 104 and 105to rotate about the bushing 112, the keys on the left hand side of thefront of the device causing the sector 105 to rotate in the direction ofthe arrow C Fig. 1, and the push keys on the right hand side of thedevice causing a movement of the sector 104 in the direction of thearrow D, Fig. 1, and as both of the arms 115 and 116 are connected tothe re spective sectors 104 and 105 the arms 115 and 116 will be causedto move in the direction of the arrow E Fig. 1.

Each sector 104 and 105 has at its lower end an extension 130 and 131respectively, which extensions overlap, as best shown in Fig. 10, andhave each a depending finger as 132 and 133, both of which are in thepath of a lever 134 pinned to a shaft 135, which passes through and isjournaled in a bearing 136 and which shaft 135 bears on its other end onthe front face of the device the lever 137 which has an enlarged upperend as 138, which lies in the path of a disk 139 borne on the end of aspindle 140, the

upper end of which bears the thumb piece 141 which is held in its upperposition by means of the spring 142 pressing against the thumb piece 141and the bottom ofa the end of the arm 9 and which passes through thehandle 144 and binds the handle to" the arm 9 by means of a shoulder145. The disk 139 is also adapted in its upper po sition to contact withand thereby be held in place so that the crank 9 cannot be moved bymeans of the stop 146 fastened to the face' plate 2 by means of thescrews 147. The stop 146 having a foot 148 which rests on the face plate2 and havinga right angled extension 149 which is perpendicular to theface plate 2, and which bears on its spindle 140.

The fingers 132 'and133 on the sectors 104 and 105 normally lie one infront of the other being bent as shown in Fig. 2 in order that they'maythus do so; 166 designates a block of insulating material fastened tothe back 1 by means of screws. 167 and 168 and bearing binding posts 169to which the diflerent wires running to the key are connected, beingpassed up through a hole not shown in the base 1 154 designates atelephone permanently connected with line wires 62 and 64.

The connections from the key to the source of current are indicated inFig. 5; therein is shown the two springs 125 and 127 as connected with astarting relay 170 in secontact is made between the springs 125 and 127the relay 170 is energized causing the armature 172 to be raised incontact with point 173, so that a circuit is then formed including thesource of current 171 through the shunt wound motor 174. The shaft 175of this motor also carries the armature windbrushes 178 and 179 areconnected. A r0 tation of the armature of motor 174 causes thegeneration of both direct and alternating current, the one of which isderived from brushes 17S and 179 and the other of The generator of which176 is the armature has a shunt field 180 which is in series with anadiustable resistance 181, the source of current 171 and the armature172 of the starting relay 170. The generator also has a series field toone terminal of which wire 59 is connected, the other terminal of thefield being connected to brush 178 and the other brush 179 beingconnected with wire 60. The brushes bearing upon the collector rings areconnected one through condensers ground at 182.

The connecting wires between spring 65 and contact 56; between spring 66and conhollow member 143, which is screwed into upper end the rightangled extension 150' which has its outer edge formed in the arc' of acircle struck from the center of the ries with a source of current 171.When ing to which the collector rings 177 and which is derived fromcollector rings 177.

to both wires 59 and 60, the other to a tact 55, etc.; in Fig. 4:, havenot been shown as such showing would merely tend to confuse, but in thediagrammatic view Fig. such connections are shown.

Operati0n.-1:tan operator at the central station desires to call any oneof a number of remote stations at each of which is a selecting devicebridged across the line wires 62 and 64, assuming the combination of thestation which it is desired to call is 3-5, the operator at the centralstation would first push in the push key 82, by so doing he wouldcompress the spring 170 and force the cone shaped member 97 against theedge of the hole in the sector 105, causing the sector to move in thedirection of the arrow C in Fig. 1 about the hub 112, which sectorhaving arm 116 rigidly attached thereto would cause a movement of lever117 so as to make a contact between springs 125 and 127,

which contact being connected in series with a source of current and arelay, the relay would thereby be energized and cause a local circuit tobe formed and cause the generators of direct current and alternatingcurrent to be put in motion and impress a direct current difference ofpotential on the wires 59 and 60, and also impress an alternatingcurrent electromotive force upon both wires of equal potential; as fullyshown, dcscribcd and claimed in applicants co-pending application SerialNo. 600,083, filed December 30th, 1911. By the depression of the key 82before mentioned, the contact between springs 67 and 72 would be broken.When the key was depressed the sector 1.05 rotated the finger 133 sothat it would be in the position as shown in Fig. 10, and would assumesuch position by virtue of the fact that the shoulder on the cone shapedmember would pass the edge of the hole in the sector 105 and the sectorwould then be thrown by the action of the s ring 121 into the positionshown in Fig. 8, thereby catch.

iug and holding the key from returning under the action of the spring170. The operator would next depress the key 92, causing in the samemanner sector 101 to rotate in the direction of the arrow D carryingwith it thearm 115, which acting upon lever 118 would cause spring 126to engage with spring 128 and also cause spring 151 to make contact withcontact spring 152 thus connecting the wires 61 and 63 with the line. Assoon as the relay above'mentioned makes contact and starts the directcurrent and alternating current generators assuming that wire 60 isconnected with the positive side of the direct current generator,current would flow through the wire 60 to the metal strip 32, then bymeans of the brushes 28 and 29 it would pass to strip 33 and by means ofthe wire 61, spring 128, spring 126 and wire 156, it would pass to theline wire 62, traveling through the line wire to all of the selectorstations through the selecting devices to the other line wire 6-1, fromwire 6 1- by means of wire 155, spring 151, contact spring 152, wire 63,strip 35, springs 31 and 30 to strip 31, passing from strip 31 by meansof the wire 59 to the negative side of the generator. The current abovetraced would cause one step of the selecting device. If the operator nowdepresses the disk 139 and thus frees it from the stop 1&6 by turn ingcrank 9 in a clock-wise direction he will cause springs 28 and 29 topass from the metallic strip 32 to the space between strip 32 and 56thereby breaking the above traced circuit, which will allow theactuating dogs of the selectors at the remote stations to return tonormal position. Continued move ment of the arm 9 would, however, causesprings 28 and 29 to contact with strips 56 and 33, thereby allowing thecurrent from the positive side of the generator to pass by means of wire60 to contact spring 72, spring 65, strip 56, brush 28, brush 29, strip33 to wire 61, contact springs 1.26 and 126 and wire 156 to line wire62, thence through the selectors at the ditlerent stations returning bymeans of the line wire 61, wire 155, spring 151, contact spring 152 andwire 63 to strip 35 and by means of springs 31 and 30 to strip 34, andby means of wire 59 to the other side of the source of current, therebycausing another movement of the selectors at the dillereut stations.Further movement of the arm 9 would again cause the current to be brokenwhen the brush 28 rested upon the insulation between strips 55 and 56and a current wouldagain be formed causing another impulse of theselecting device when the brush- 28 bore upon the strip 55.

Further movement of the arm- 9 would cause no further movements of theselector devices until the spring 23 bore upon the contact strip 19, forby the push key 82 contact between springs 67 and 72 is broken so that.no further impulse will be caused by brush 28 bearing upon strips 51,52, 51 and 50. As soon as brush 30 bears upon strip 41 a circuit isformed thus: wire 60, strip 32, connector 58, strip 41, brush 30, brush31, strip 35, wire 63, contact springs 152 and 151, wire 155, line wire61 to and through the selectors to the different stations, returning byline wire 62, wire 156, springs 126 and 128, wire 61, strip 33, brush 2,brush 28, strip 49, connector 57, strip 3- 1 and wire 59 to the otherside of the source of current. It will be noticed that in the circuitlast described the direction of current ,is reversed from that firstused to actuate the selector devices, for in the circuit previouslydescribed the positive current flows from the transmitting key to linewire 62, but it now flows from the transmitting key to the line wire6st, thus the current supply to the line wires has been reversed inpohr-i-ty, and consequently will have a different action upon theselector at the remote stations. As the arm 9 further rotated thecircuit will be made and broken until the springs pass the strip 45,after which. no -'cir cuit will be formed as the springs 72 and- 77 wereseparated by the depression of key 92. When the brush 28 again contactswith strip 32 a circuit will-be formed as follows: from the positiveside of the generator wire '60, strip 32, brushes 2B and '29,

strip 33, wire 61, contact springs 1'28 and to cause a local contact tobe closed at the. I particular station, whose combination is 3 5, in amanner fully shown, described and claimed in applicants co-pend-ingapplication, Serial l\ 596,252, filed December 8, 1910. As soon as thelocal contact is closed the alternating cur-rent from one pole of thesource of alternating current connect. ed to both line wires 59 and 60flows "by wire 59 to'strip 34, brush'30, brush 31, strip 35, wire 63,contact springs 152 and 151 and wire 155 to line wire 64;, it also flowsby means of wire 60 to strip 32, brush 28,,

brush 29, strip 33, wire 61, contact springs 128 and 126, wire 156 toline wire 62. The current then travels to the remote station at whichthe local contact was closed in a manner fully shown, described andclaimed in zqtrplicants co-pending application Serial No. 600,083 abovereferred to, to actuate an alarm device, returning to the alternatingsourceof current by means of a wire from the alarm device connected tothe ground, the-opposite pole of the source at the central station fromthat to which the wires 59 and '60 are connected being also connected tothe ground in order to complete the return path.

The operator continues to rotate the arm 9 until the disk 139 comes incontact with the projection 138 on the lever 137, during the entiretimeof which movement from the beginning strip 32 the alarm at the remotestation continues to ring. A further movement of the arm 9 causes thelever 137 to be moved in the direction indicated by arrow E in Fig. 1,which as it is rigidlyconnected to lever 134 causes a correspond-- ingmovement in said lever and as the lever 134: is retated it bears againstfingers 132 and 133 on the sectors 104-an'd 105 respectively, causingthe said sectors to both rotate about the shaft 8 in a direction indirated by arrow D in Fig. 1, andthe fingers 132 and 133 assume theposition as shown in Fig. 12, which causes the holes 103' in.

said sectors to aline with the circular base on the cone 97, therebyallowing the spring 170 to project the keys 82 and 92 into their normaloutward position. If the operator continues to hold the thumb piece 141depressed the lever 137 will be held at the limit of its motion in thedirection of arrow E, Fig. 1 and the alarm at the remote station willcontinue to ring, but as soon as the operatorreleases the thumb piece141 the.

spring 142 will project it outwardly thereby freeing the lever 137 whichwill return to its normal position as shown in Fig. 1 by virtue of thefact that the tension springs 124 bear on the levers 117 and 118, whichin turn by means of "their bifurcated ends act on the levers 115 and 116in a direction to rotate the sectors to which the said levers areattached in the direction of the arrow F, as shown in Fig. 1. As soon assuch movement is completed the springs'125 and 127 break cont-act, beingno longer pressed together by the lever 117, and at the same timesprings 126, 128, 151 and 152 break contact-a consequencerof which isthat the relay is de'nergized, the generator stops, and the line wiresare disconnected from the transmitting key, it being obvious that thealarm at the remote station "ceases to ring at the Same moment that thecontact springs shift.

It is to be observed that throughout the entire revolution of the arm 9the gear 11 has moved with it, rotating the pinion 12 and through it thegear 13, which is in mesh with the pinion 14 bearing the friction shoes18-, so that if the operator attempts to rotate the crank arm 9 at anexcessive rate of speed the shoes 18*18 are by action of centrifugalforce thrown outwardly against the tension of the springs 19 and bearagainst the friction drum 21,- so that the faster the operator attemptsto turn the crank the greater the friction on the drum 21-, and it canbe' readily understood that the tension of the springs 19 can be soadjusted as to oblige the operator to always turn the handle below acertain speed. 1

It should be observed that the push key 87 does not control a contactsimilar to 65, 66, etc, so that when it is depressed the converter isstarted and the maximum number of impulses is transmitted from the keyin one direction. When push key 95 is depressed, the key is connected tothe line and the maximum number of impulses in an opposite direction aresent.

We wish'i-t to be understood that we do not desire to be limited to theexact details of construction shown and described, for the obviousmodifications will occur to a person skilled in the art.

Having articularly described the construction o? embodiment of ourinvention and explained the operation and principle thereof, what weclaim as new and desireto protect by Letters Patent 1s:--

1. In a selective calling key, a normally inactive converter, amanuallyoperable means for starting the normally inactive converter, anindependently manually operable means for transmitting a; number ofimpulses of electricity from said converter and means caused to actautomatically by I said second named meansto return said firstconverter, indepen ently manually operable means for transmitting anumber of impulses of electricity from said converter in onedirection,.then a number in the other direction, then one in the firstsaid direction and means caused to act automatically by said secondnamed means to return said first named means to unoperated position.

v 4.111 a selective calling key, in combination, normally open contacts,means for closing the contacts, a pivoted member connected to said meansfor closing them, a spring pressed push key for operating said pivotedmember, said push key and pivoted member having coiiperating partswhereby said pivoted member prevents the return of said push key afterbeing pushed, and said push key holds said pivoted member in movedposition, means for utilizing said contacts, and means for returning thepivoted member and the push keys to their original positions.

5. In a selective calling key, in combination. normally open contacts,means for clos ing the contacts, a. pivoted member connected to saidmeans for closing them, a spring pressed push key for operating saidpivoted member, said push key and pivoted member having cotiperatingparts whereby said pivoted member prevents the return of said push keyafter being pushed, and said push key holds said pivoted member in amoved position, a source of current operatively connected to the key bythe closing of said normally open contacts, manually operable means totransmit said current in impulses from the key, means acted upon by saidlast invents (l7 I named means to cause a movement of said pivotedmember for releasing said push key to allow it to return to unoperatedcondition.

6. in a selective calling key, manually operable means for transmittinga number of impulses of electricity 1n one direction, then a number inan opposite direction, then one impulse in the first said directionmeans actuated by a single manual motion ior pro: determining the numberof the first said 1mpulses and for starting a normally inactiveconverter for supplying electrical energy for all the above mentionserable by a single manual. motion for connecting said first named meanswith a transimpulses, means Op,

mission line and for predetermining the y number of said impulses in anopposite direction, and means operated automatically by the first namedmanually o erable means for returning said second an mentioned means tounoperated position.

'2. in a selective calling key, a normally inactive converter, amanually operable third above means for starting the normally inactiveconverter, an independently manually operable means for connecting thekey to a transmission line, an independently manually operable means fortransmitting a numher of impulses of electricity from said converter tosaid line and means caused to act automatically by said last named meansto return both said first and said second named means to unoperated'position.

8. In a selective calling key, in combination, normally open contactsconnected to a starting devise, a lever for closing the contacts, asector for moving the lever, push keys for moving the sector, a seriesof normally closed contacts corresponding with the keys, means connectedto each of the push keys for breakin its normally closed contact, asecond set 0 push keys, a second sector moved thereby, a second seriesof normally closed contacts corresponding with the second said set ofpush keys, a lever connected to said second sector, two sets of normallyopen contacts controlled thereby, connections from said contacts on oneside to line wires, connections from the other side of said contacts,metallic strips connected therewith, other metallic strips, brushesadapted to contact the metallic strips, a shaft bearing the brushes, acrank for turning the shaft.

9. In a selective calling key, in combination, a source of current, anannular metallic strip having a connection, withan external system,another annular strip having a connection with an external system,segmental strips connected to said source of current, other segmentalstrips, connections from the said source of currentto each of said otherstrips, normally closed contacts in the connections to certain of saidstrips,

will, normally open contacts in the circuit of a starting device,normally open contacts in the connections of'the annular strips to anexternal system, and means comprising push keys for breaking the saidnormally closed contacts and closing the saidv normally open contacts.

10.- In a'selective calling key, a normally inactive converter, manuallyoperable means for starting the normally inactive converter, manuallyoperable means for connecting the key with a transmission line, manuallvoperable means to impress upon the line a predetermined fixed number ofimpulses of electricity from said converter in one direction, then apredetermined fixed number in the opposite direction, then one in thefirst said direction and means then caused to act automatically by theimpulse impressing means to stop the started converter and disconnectthe key from the transmission line. I

11. In a selective calling key, manually operable means for transmittinga number of impulses of electricity, means actuated by a single manualmotion for predetermining the number of the impulses and for starting anormally inactive converter for supplying electrical energy for theimpulses, means operated automatically by said first named means forreturning said second named means to unoperated position.

12. In a selective calling key, two ivoted members, means to rotate one0 said members, means to rotate the other of said Copies of this patentmay be obtained for five cents each, by addressing the members, vmeansconstantly tending rotate 'both' said-members to normal posltion,

ber-on sai, stem, a finger rest on the stem,

spring means to hold the stem, cone'shaped member, and finger restnormally 1n one po sition, a pivoted member for each set of keys havinga hole therethrough under the cone shaped member, said hole belng ofsuch a size that the cone shaped member may pass therethrough, the coneshapedmember normally resting on an edge of the hole, the depression ofthe cone shaped member causing a rotation of its pivoted mem; ber, meansacting upon the pivoted meme? bers to cause them to engage the base ofthe corresponding cone shaped member when the cone shaped member isdepressed and prevent the return of the cone shaped member, and meansincluding a pivoted member for moving the first mentioned pivotedmembers to allow their spring actuated cone shaped members to return tonormal positio MAURICE F. GEER.

RICHARD C. LEAIH Witnesses:

ROBINA J. HAIRE, LJLLIAN L. Pnnmrrs.

commissioner of Patents,

